1 /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*-
2 * vim:expandtab:shiftwidth=8:tabstop=8:
4 * Copyright (c) 2001-2003 Cluster File Systems, Inc.
6 * This file is part of Lustre, http://www.lustre.org.
8 * Lustre is free software; you can redistribute it and/or
9 * modify it under the terms of version 2 of the GNU General Public
10 * License as published by the Free Software Foundation.
12 * Lustre is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with Lustre; if not, write to the Free Software
19 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
23 #include <linux/sched.h>
24 #include <linux/smp_lock.h>
25 #include <linux/quotaops.h>
27 #define DEBUG_SUBSYSTEM S_LLITE
29 #include <obd_support.h>
30 #include <lustre_lite.h>
31 #include <lustre/lustre_idl.h>
32 #include <lustre_dlm.h>
33 #include <lustre_mdc.h>
34 //#include <lustre_ver.h>
35 //#include <lustre_version.h>
37 #include "llite_internal.h"
39 /* should NOT be called with the dcache lock, see fs/dcache.c */
40 static void ll_release(struct dentry *de)
42 struct ll_dentry_data *lld;
46 if (lld == NULL) { /* NFS copies the de->d_op methods (bug 4655) */
50 #ifndef HAVE_VFS_INTENT_PATCHES
52 ll_intent_release(lld->lld_it);
53 OBD_FREE(lld->lld_it, sizeof(*lld->lld_it));
56 LASSERT(lld->lld_cwd_count == 0);
57 LASSERT(lld->lld_mnt_count == 0);
58 OBD_FREE(de->d_fsdata, sizeof(*lld));
63 #ifdef DCACHE_LUSTRE_INVALID
64 /* Compare if two dentries are the same. Don't match if the existing dentry
65 * is marked DCACHE_LUSTRE_INVALID. Returns 1 if different, 0 if the same.
67 * This avoids a race where ll_lookup_it() instantiates a dentry, but we get
68 * an AST before calling d_revalidate_it(). The dentry still exists (marked
69 * INVALID) so d_lookup() matches it, but we have no lock on it (so
70 * lock_match() fails) and we spin around real_lookup(). */
71 int ll_dcompare(struct dentry *parent, struct qstr *d_name, struct qstr *name)
73 struct dentry *dchild;
76 if (d_name->len != name->len)
79 if (memcmp(d_name->name, name->name, name->len))
82 /* XXX: d_name must be in-dentry structure */
83 dchild = container_of(d_name, struct dentry, d_name); /* ugh */
84 if (dchild->d_flags & DCACHE_LUSTRE_INVALID) {
85 CDEBUG(D_DENTRY,"INVALID dentry %p not matched, was bug 3784\n",
94 /* should NOT be called with the dcache lock, see fs/dcache.c */
95 static int ll_ddelete(struct dentry *de)
99 #ifndef DCACHE_LUSTRE_INVALID
100 #define DCACHE_LUSTRE_INVALID 0
103 CDEBUG(D_DENTRY, "%s dentry %.*s (%p, parent %p, inode %p) %s%s\n",
104 (de->d_flags & DCACHE_LUSTRE_INVALID ? "deleting" : "keeping"),
105 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
106 d_unhashed(de) ? "" : "hashed,",
107 list_empty(&de->d_subdirs) ? "" : "subdirs");
108 #if DCACHE_LUSTRE_INVALID == 0
109 #undef DCACHE_LUSTRE_INVALID
115 void ll_set_dd(struct dentry *de)
120 CDEBUG(D_DENTRY, "ldd on dentry %.*s (%p) parent %p inode %p refc %d\n",
121 de->d_name.len, de->d_name.name, de, de->d_parent, de->d_inode,
122 atomic_read(&de->d_count));
124 if (de->d_fsdata == NULL) {
125 OBD_ALLOC(de->d_fsdata, sizeof(struct ll_dentry_data));
132 void ll_intent_drop_lock(struct lookup_intent *it)
134 struct lustre_handle *handle;
136 if (it->it_op && it->d.lustre.it_lock_mode) {
137 handle = (struct lustre_handle *)&it->d.lustre.it_lock_handle;
138 CDEBUG(D_DLMTRACE, "releasing lock with cookie "LPX64
139 " from it %p\n", handle->cookie, it);
140 ldlm_lock_decref(handle, it->d.lustre.it_lock_mode);
142 /* bug 494: intent_release may be called multiple times, from
143 * this thread and we don't want to double-decref this lock */
144 it->d.lustre.it_lock_mode = 0;
148 void ll_intent_release(struct lookup_intent *it)
152 CDEBUG(D_INFO, "intent %p released\n", it);
153 ll_intent_drop_lock(it);
154 #ifdef HAVE_VFS_INTENT_PATCHES
156 it->it_op_release = 0;
158 /* We are still holding extra reference on a request, need to free it */
159 if (it_disposition(it, DISP_ENQ_OPEN_REF)) /* open req for llfile_open*/
160 ptlrpc_req_finished(it->d.lustre.it_data);
161 if (it_disposition(it, DISP_ENQ_CREATE_REF)) /* create rec */
162 ptlrpc_req_finished(it->d.lustre.it_data);
163 if (it_disposition(it, DISP_ENQ_COMPLETE)) /* saved req from revalidate
165 ptlrpc_req_finished(it->d.lustre.it_data);
167 it->d.lustre.it_disposition = 0;
168 it->d.lustre.it_data = NULL;
172 /* Drop dentry if it is not used already, unhash otherwise.
173 Should be called with dcache lock held!
174 Returns: 1 if dentry was dropped, 0 if unhashed. */
175 int ll_drop_dentry(struct dentry *dentry)
178 if (atomic_read(&dentry->d_count) == 0) {
179 CDEBUG(D_DENTRY, "deleting dentry %.*s (%p) parent %p "
180 "inode %p\n", dentry->d_name.len,
181 dentry->d_name.name, dentry, dentry->d_parent,
185 unlock_dentry(dentry);
186 spin_unlock(&dcache_lock);
188 spin_lock(&dcache_lock);
191 /* disconected dentry can not be find without lookup, because we
192 * not need his to unhash or mark invalid. */
193 if (dentry->d_flags & DCACHE_DISCONNECTED) {
194 unlock_dentry(dentry);
198 #ifdef DCACHE_LUSTRE_INVALID
199 if (!(dentry->d_flags & DCACHE_LUSTRE_INVALID)) {
201 if (!d_unhashed(dentry)) {
203 CDEBUG(D_DENTRY, "unhashing dentry %.*s (%p) parent %p "
204 "inode %p refc %d\n", dentry->d_name.len,
205 dentry->d_name.name, dentry, dentry->d_parent,
206 dentry->d_inode, atomic_read(&dentry->d_count));
207 /* actually we don't unhash the dentry, rather just
208 * mark it inaccessible for to __d_lookup(). otherwise
209 * sys_getcwd() could return -ENOENT -bzzz */
210 #ifdef DCACHE_LUSTRE_INVALID
211 dentry->d_flags |= DCACHE_LUSTRE_INVALID;
213 if (!dentry->d_inode || !S_ISDIR(dentry->d_inode->i_mode))
217 unlock_dentry(dentry);
221 void ll_unhash_aliases(struct inode *inode)
223 struct list_head *tmp, *head;
227 CERROR("unexpected NULL inode, tell phil\n");
231 CDEBUG(D_INODE, "marking dentries for ino %lu/%u(%p) invalid\n",
232 inode->i_ino, inode->i_generation, inode);
234 head = &inode->i_dentry;
235 spin_lock(&dcache_lock);
238 while ((tmp = tmp->next) != head) {
239 struct dentry *dentry = list_entry(tmp, struct dentry, d_alias);
241 CDEBUG(D_DENTRY, "dentry in drop %.*s (%p) parent %p "
242 "inode %p flags %d\n", dentry->d_name.len,
243 dentry->d_name.name, dentry, dentry->d_parent,
244 dentry->d_inode, dentry->d_flags);
246 if (dentry->d_name.len == 1 && dentry->d_name.name[0] == '/') {
247 CERROR("called on root (?) dentry=%p, inode=%p "
248 "ino=%lu\n", dentry, inode, inode->i_ino);
249 lustre_dump_dentry(dentry, 1);
250 libcfs_debug_dumpstack(NULL);
251 } else if (d_mountpoint(dentry)) {
252 /* For mountpoints we skip removal of the dentry
253 which happens solely because we have a lock on it
254 obtained when this dentry was not a mountpoint yet */
255 CDEBUG(D_DENTRY, "Skippind mountpoint dentry removal "
256 "%.*s (%p) parent %p\n",
259 dentry, dentry->d_parent);
264 if (ll_drop_dentry(dentry))
267 spin_unlock(&dcache_lock);
271 int ll_revalidate_it_finish(struct ptlrpc_request *request,
272 int offset, struct lookup_intent *it,
281 if (it_disposition(it, DISP_LOOKUP_NEG))
284 rc = ll_prep_inode(&de->d_inode,
285 request, offset, NULL);
290 void ll_lookup_finish_locks(struct lookup_intent *it, struct dentry *dentry)
293 LASSERT(dentry != NULL);
295 if (it->d.lustre.it_lock_mode && dentry->d_inode != NULL) {
296 struct inode *inode = dentry->d_inode;
297 struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode);
299 CDEBUG(D_DLMTRACE, "setting l_data to inode %p (%lu/%u)\n",
300 inode, inode->i_ino, inode->i_generation);
301 md_set_lock_data(sbi->ll_md_exp, &it->d.lustre.it_lock_handle,
305 /* drop lookup or getattr locks immediately */
306 if (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR) {
307 /* on 2.6 there are situation when several lookups and
308 * revalidations may be requested during single operation.
309 * therefore, we don't release intent here -bzzz */
310 ll_intent_drop_lock(it);
314 void ll_frob_intent(struct lookup_intent **itp, struct lookup_intent *deft)
316 struct lookup_intent *it = *itp;
317 #ifdef HAVE_VFS_INTENT_PATCHES
319 LASSERTF(it->it_magic == INTENT_MAGIC,
320 "%p has bad intent magic: %x\n",
325 if (!it || it->it_op == IT_GETXATTR)
328 #ifdef HAVE_VFS_INTENT_PATCHES
329 it->it_op_release = ll_intent_release;
333 int ll_revalidate_it(struct dentry *de, int lookup_flags,
334 struct lookup_intent *it)
337 struct md_op_data *op_data;
338 struct ptlrpc_request *req = NULL;
339 struct lookup_intent lookup_it = { .it_op = IT_LOOKUP };
340 struct obd_export *exp;
341 struct inode *parent;
344 CDEBUG(D_VFSTRACE, "VFS Op:name=%s,intent=%s\n", de->d_name.name,
347 if (de->d_inode == NULL) {
348 /* We can only use negative dentries if this is stat or lookup,
349 for opens and stuff we do need to query server. */
350 /* If there is IT_CREAT in intent op set, then we must throw
351 away this negative dentry and actually do the request to
352 kernel to create whatever needs to be created (if possible)*/
353 if (it && (it->it_op & IT_CREAT))
356 #ifdef DCACHE_LUSTRE_INVALID
357 if (de->d_flags & DCACHE_LUSTRE_INVALID)
361 rc = ll_have_md_lock(de->d_parent->d_inode,
362 MDS_INODELOCK_UPDATE);
367 exp = ll_i2mdexp(de->d_inode);
369 /* Never execute intents for mount points.
370 * Attributes will be fixed up in ll_inode_revalidate_it */
371 if (d_mountpoint(de))
374 /* Root of the lustre tree. Always valid.
375 * Attributes will be fixed up in ll_inode_revalidate_it */
376 if (de == de->d_sb->s_root)
379 OBD_FAIL_TIMEOUT(OBD_FAIL_MDC_REVALIDATE_PAUSE, 5);
380 ll_frob_intent(&it, &lookup_it);
383 parent = de->d_parent->d_inode;
385 if (it->it_op & IT_CREAT) {
386 op_data = ll_prep_md_op_data(NULL, parent, NULL,
387 de->d_name.name, de->d_name.len,
388 0, LUSTRE_OPC_CREATE, NULL);
390 op_data = ll_prep_md_op_data(NULL, parent, de->d_inode,
391 de->d_name.name, de->d_name.len,
392 0, LUSTRE_OPC_ANY, NULL);
395 RETURN(PTR_ERR(op_data));
397 if ((it->it_op == IT_OPEN) && de->d_inode) {
398 struct inode *inode = de->d_inode;
399 struct ll_inode_info *lli = ll_i2info(inode);
400 struct obd_client_handle **och_p;
404 * We used to check for MDS_INODELOCK_OPEN here, but in fact
405 * just having LOOKUP lock is enough to justify inode is the
406 * same. And if inode is the same and we have suitable
407 * openhandle, then there is no point in doing another OPEN RPC
408 * just to throw away newly received openhandle. There are no
409 * security implications too, if file owner or access mode is
410 * change, LOOKUP lock is revoked.
414 if (it->it_flags & FMODE_WRITE) {
415 och_p = &lli->lli_mds_write_och;
416 och_usecount = &lli->lli_open_fd_write_count;
417 } else if (it->it_flags & FMODE_EXEC) {
418 och_p = &lli->lli_mds_exec_och;
419 och_usecount = &lli->lli_open_fd_exec_count;
421 och_p = &lli->lli_mds_read_och;
422 och_usecount = &lli->lli_open_fd_read_count;
424 /* Check for the proper lock. */
425 if (!ll_have_md_lock(inode, MDS_INODELOCK_LOOKUP))
427 down(&lli->lli_och_sem);
428 if (*och_p) { /* Everything is open already, do nothing */
429 /*(*och_usecount)++; Do not let them steal our open
430 handle from under us */
431 /* XXX The code above was my original idea, but in case
432 we have the handle, but we cannot use it due to later
433 checks (e.g. O_CREAT|O_EXCL flags set), nobody
434 would decrement counter increased here. So we just
435 hope the lock won't be invalidated in between. But
436 if it would be, we'll reopen the open request to
437 MDS later during file open path */
438 up(&lli->lli_och_sem);
439 ll_finish_md_op_data(op_data);
442 up(&lli->lli_och_sem);
447 it->it_create_mode &= ~current->fs->umask;
448 it->it_flags |= O_CHECK_STALE;
449 rc = md_intent_lock(exp, op_data, NULL, 0, it,
451 &req, ll_md_blocking_ast, 0);
452 it->it_flags &= ~O_CHECK_STALE;
453 ll_finish_md_op_data(op_data);
454 /* If req is NULL, then md_intent_lock only tried to do a lock match;
455 * if all was well, it will return 1 if it found locks, 0 otherwise. */
456 if (req == NULL && rc >= 0) {
464 CDEBUG(D_INFO, "ll_intent_lock: rc %d : it->it_status "
465 "%d\n", rc, it->d.lustre.it_status);
471 rc = ll_revalidate_it_finish(req, DLM_REPLY_REC_OFF, it, de);
473 if (rc != -ESTALE && rc != -ENOENT)
474 ll_intent_release(it);
478 if ((it->it_op & IT_OPEN) && de->d_inode &&
479 !S_ISREG(de->d_inode->i_mode) &&
480 !S_ISDIR(de->d_inode->i_mode)) {
481 ll_release_openhandle(de, it);
485 /* unfortunately ll_intent_lock may cause a callback and revoke our
487 spin_lock(&dcache_lock);
492 spin_unlock(&dcache_lock);
495 /* We do not free request as it may be reused during following lookup
496 * (see comment in mdc/mdc_locks.c::mdc_intent_lock()), request will
497 * be freed in ll_lookup_it or in ll_intent_release. But if
498 * request was not completed, we need to free it. (bug 5154, 9903) */
499 if (req != NULL && !it_disposition(it, DISP_ENQ_COMPLETE))
500 ptlrpc_req_finished(req);
502 #ifdef DCACHE_LUSTRE_INVALID
503 ll_unhash_aliases(de->d_inode);
504 /* done in ll_unhash_aliases()
505 dentry->d_flags |= DCACHE_LUSTRE_INVALID; */
507 /* We do not want d_invalidate to kill all child dentries too */
511 CDEBUG(D_DENTRY, "revalidated dentry %.*s (%p) parent %p "
512 "inode %p refc %d\n", de->d_name.len,
513 de->d_name.name, de, de->d_parent, de->d_inode,
514 atomic_read(&de->d_count));
515 ll_lookup_finish_locks(it, de);
516 #ifdef DCACHE_LUSTRE_INVALID
518 de->d_flags &= ~DCACHE_LUSTRE_INVALID;
525 * This part is here to combat evil-evil race in real_lookup on 2.6
526 * kernels. The race details are: We enter do_lookup() looking for some
527 * name, there is nothing in dcache for this name yet and d_lookup()
528 * returns NULL. We proceed to real_lookup(), and while we do this,
529 * another process does open on the same file we looking up (most simple
530 * reproducer), open succeeds and the dentry is added. Now back to
531 * us. In real_lookup() we do d_lookup() again and suddenly find the
532 * dentry, so we call d_revalidate on it, but there is no lock, so
533 * without this code we would return 0, but unpatched real_lookup just
534 * returns -ENOENT in such a case instead of retrying the lookup. Once
535 * this is dealt with in real_lookup(), all of this ugly mess can go and
536 * we can just check locks in ->d_revalidate without doing any RPCs
540 if (it != &lookup_it) {
541 /* MDS_INODELOCK_UPDATE needed for IT_GETATTR case. */
542 if (it->it_op == IT_GETATTR)
543 lookup_it.it_op = IT_GETATTR;
544 ll_lookup_finish_locks(it, de);
548 /* Do real lookup here. */
549 op_data = ll_prep_md_op_data(NULL, parent, NULL, de->d_name.name,
550 de->d_name.len, 0, (it->it_op & IT_CREAT ?
552 LUSTRE_OPC_ANY), NULL);
554 RETURN(PTR_ERR(op_data));
556 rc = md_intent_lock(exp, op_data, NULL, 0, it, 0, &req,
557 ll_md_blocking_ast, 0);
559 struct mdt_body *mdt_body = lustre_msg_buf(req->rq_repmsg,
562 struct lu_fid fid = {.f_seq = 0, .f_oid = 0, .f_ver = 0};
565 fid = *ll_inode2fid(de->d_inode);
567 /* see if we got same inode, if not - return error */
568 if (lu_fid_eq(&fid, &mdt_body->fid1)) {
569 ll_finish_md_op_data(op_data);
571 goto revalidate_finish;
573 ll_intent_release(it);
575 ll_finish_md_op_data(op_data);
579 /*static*/ void ll_pin(struct dentry *de, struct vfsmount *mnt, int flag)
581 struct inode *inode= de->d_inode;
582 struct ll_sb_info *sbi = ll_i2sbi(inode);
583 struct ll_dentry_data *ldd = ll_d2d(de);
584 struct obd_client_handle *handle;
591 /* Strictly speaking this introduces an additional race: the
592 * increments should wait until the rpc has returned.
593 * However, given that at present the function is void, this
595 if (flag == 1 && (++ldd->lld_mnt_count) > 1) {
601 if (flag == 0 && (++ldd->lld_cwd_count) > 1) {
608 handle = (flag) ? &ldd->lld_mnt_och : &ldd->lld_cwd_och;
609 oc = ll_mdscapa_get(inode);
610 rc = obd_pin(sbi->ll_md_exp, ll_inode2fid(inode), oc, handle, flag);
614 memset(handle, 0, sizeof(*handle));
616 ldd->lld_cwd_count--;
618 ldd->lld_mnt_count--;
626 /*static*/ void ll_unpin(struct dentry *de, struct vfsmount *mnt, int flag)
628 struct ll_sb_info *sbi = ll_i2sbi(de->d_inode);
629 struct ll_dentry_data *ldd = ll_d2d(de);
630 struct obd_client_handle handle;
636 /* Strictly speaking this introduces an additional race: the
637 * increments should wait until the rpc has returned.
638 * However, given that at present the function is void, this
640 handle = (flag) ? ldd->lld_mnt_och : ldd->lld_cwd_och;
641 if (handle.och_magic != OBD_CLIENT_HANDLE_MAGIC) {
642 /* the "pin" failed */
649 count = --ldd->lld_mnt_count;
651 count = --ldd->lld_cwd_count;
659 rc = obd_unpin(sbi->ll_md_exp, &handle, flag);
664 #ifdef HAVE_VFS_INTENT_PATCHES
665 static int ll_revalidate_nd(struct dentry *dentry, struct nameidata *nd)
670 if (nd && nd->flags & LOOKUP_LAST && !(nd->flags & LOOKUP_LINK_NOTLAST))
671 rc = ll_revalidate_it(dentry, nd->flags, &nd->intent);
673 rc = ll_revalidate_it(dentry, 0, NULL);
678 int ll_revalidate_nd(struct dentry *dentry, struct nameidata *nd)
683 if (nd && !(nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))) {
684 struct lookup_intent *it;
685 it = ll_convert_intent(&nd->intent.open, nd->flags);
688 if (it->it_op == (IT_OPEN|IT_CREAT))
689 if (nd->intent.open.flags & O_EXCL) {
690 CDEBUG(D_VFSTRACE, "create O_EXCL, returning 0\n");
695 rc = ll_revalidate_it(dentry, nd->flags, it);
697 if (rc && (nd->flags & LOOKUP_OPEN) &&
698 it_disposition(it, DISP_OPEN_OPEN)) {/*Open*/
699 #ifdef HAVE_FILE_IN_STRUCT_INTENT
700 // XXX Code duplication with ll_lookup_nd
701 if (S_ISFIFO(dentry->d_inode->i_mode)) {
702 // We cannot call open here as it would
705 (struct ptlrpc_request *)
706 it->d.lustre.it_data);
710 nd->intent.open.file->private_data = it;
711 filp = lookup_instantiate_filp(nd, dentry,NULL);
712 #if (LINUX_VERSION_CODE < KERNEL_VERSION(2,6,17))
713 /* 2.6.1[456] have a bug in open_namei() that forgets to check
714 * nd->intent.open.file for error, so we need to return it as lookup's result
721 ll_release_openhandle(dentry, it);
722 #endif /* HAVE_FILE_IN_STRUCT_INTENT */
724 if (!rc && (nd->flags & LOOKUP_CREATE) &&
725 it_disposition(it, DISP_OPEN_CREATE)) {
726 /* We created something but we may only return
727 * negative dentry here, so save request in dentry,
728 * if lookup will be called later on, it will
729 * pick the request, otherwise it would be freed
731 ll_d2d(dentry)->lld_it = it;
732 it = NULL; /* avoid freeing */
737 ll_intent_release(it);
738 OBD_FREE(it, sizeof(*it));
741 rc = ll_revalidate_it(dentry, 0, NULL);
748 struct dentry_operations ll_d_ops = {
749 .d_revalidate = ll_revalidate_nd,
750 .d_release = ll_release,
751 .d_delete = ll_ddelete,
752 #ifdef DCACHE_LUSTRE_INVALID
753 .d_compare = ll_dcompare,