4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License version 2 only,
8 * as published by the Free Software Foundation.
10 * This program is distributed in the hope that it will be useful, but
11 * WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * General Public License version 2 for more details (a copy is included
14 * in the LICENSE file that accompanied this code).
16 * You should have received a copy of the GNU General Public License
17 * version 2 along with this program; If not, see
18 * http://www.gnu.org/licenses/gpl-2.0.html
23 * Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Use is subject to license terms.
26 * Copyright (c) 2011, 2017, Intel Corporation.
29 * This file is part of Lustre, http://www.lustre.org/
30 * Lustre is a trademark of Sun Microsystems, Inc.
34 #include <linux/sched.h>
35 #include <linux/quotaops.h>
36 #include <linux/kernel.h>
38 #define DEBUG_SUBSYSTEM S_LLITE
40 #include <obd_support.h>
41 #include <lustre_dlm.h>
43 #include "llite_internal.h"
45 static void free_dentry_data(struct rcu_head *head)
47 struct ll_dentry_data *lld;
49 lld = container_of(head, struct ll_dentry_data, lld_rcu_head);
53 /* should NOT be called with the dcache lock, see fs/dcache.c */
54 static void ll_release(struct dentry *de)
56 struct ll_dentry_data *lld;
60 if (lld == NULL) /* NFS copies the de->d_op methods (bug 4655) */
64 call_rcu(&lld->lld_rcu_head, free_dentry_data);
69 /* Compare if two dentries are the same. Don't match if the existing dentry
70 * is marked invalid. Returns 1 if different, 0 if the same.
72 * This avoids a race where ll_lookup_it() instantiates a dentry, but we get
73 * an AST before calling d_revalidate_it(). The dentry still exists (marked
74 * INVALID) so d_lookup() matches it, but we have no lock on it (so
75 * lock_match() fails) and we spin around real_lookup().
77 * This race doesn't apply to lookups in d_alloc_parallel(), and for
78 * those we want to ensure that only one dentry with a given name is
79 * in ll_lookup_nd() at a time. So allow invalid dentries to match
80 * while d_in_lookup(). We will be called again when the lookup
81 * completes, and can give a different answer then.
83 #if defined(HAVE_D_COMPARE_5ARGS)
84 static int ll_dcompare(const struct dentry *parent, const struct dentry *dentry,
85 unsigned int len, const char *str,
86 const struct qstr *name)
87 #elif defined(HAVE_D_COMPARE_4ARGS)
88 static int ll_dcompare(const struct dentry *dentry, unsigned int len,
89 const char *str, const struct qstr *name)
97 if (memcmp(str, name->name, len))
100 CDEBUG(D_DENTRY, "found name %.*s(%p) flags %#x refc %d\n",
101 name->len, name->name, dentry, dentry->d_flags,
104 /* mountpoint is always valid */
105 if (d_mountpoint((struct dentry *)dentry))
108 /* ensure exclusion against parallel lookup of the same name */
109 if (d_in_lookup((struct dentry *)dentry))
112 if (d_lustre_invalid(dentry))
119 * Called when last reference to a dentry is dropped and dcache wants to know
120 * whether or not it should cache it:
121 * - return 1 to delete the dentry immediately
122 * - return 0 to cache the dentry
123 * Should NOT be called with the dcache lock, see fs/dcache.c
125 static int ll_ddelete(const struct dentry *de)
130 CDEBUG(D_DENTRY, "%s dentry %pd (%p, parent %p, inode %p) %s%s\n",
131 d_lustre_invalid((struct dentry *)de) ? "deleting" : "keeping",
132 de, de, de->d_parent, de->d_inode,
133 d_unhashed((struct dentry *)de) ? "" : "hashed,",
134 list_empty(&de->d_subdirs) ? "" : "subdirs");
136 /* kernel >= 2.6.38 last refcount is decreased after this function. */
137 LASSERT(ll_d_count(de) == 1);
139 if (d_lustre_invalid((struct dentry *)de))
144 int ll_d_init(struct dentry *de)
149 CDEBUG(D_DENTRY, "ldd on dentry %pd (%p) parent %p inode %p refc %d\n",
150 de, de, de->d_parent, de->d_inode,
153 if (de->d_fsdata == NULL) {
154 struct ll_dentry_data *lld;
157 if (likely(lld != NULL)) {
158 spin_lock(&de->d_lock);
159 if (likely(de->d_fsdata == NULL)) {
161 __d_lustre_invalidate(de);
165 spin_unlock(&de->d_lock);
170 LASSERT(de->d_op == &ll_d_ops);
175 void ll_intent_drop_lock(struct lookup_intent *it)
177 if (it->it_op && it->it_lock_mode) {
178 struct lustre_handle handle;
180 handle.cookie = it->it_lock_handle;
182 CDEBUG(D_DLMTRACE, "releasing lock with cookie %#llx from it %p\n",
184 ldlm_lock_decref(&handle, it->it_lock_mode);
186 /* bug 494: intent_release may be called multiple times, from
187 * this thread and we don't want to double-decref this lock */
188 it->it_lock_mode = 0;
189 if (it->it_remote_lock_mode != 0) {
190 handle.cookie = it->it_remote_lock_handle;
193 "releasing remote lock with cookie %#llx from it %p\n",
195 ldlm_lock_decref(&handle,
196 it->it_remote_lock_mode);
197 it->it_remote_lock_mode = 0;
202 void ll_intent_release(struct lookup_intent *it)
206 CDEBUG(D_INFO, "intent %p released\n", it);
207 ll_intent_drop_lock(it);
208 /* We are still holding extra reference on a request, need to free it */
209 if (it_disposition(it, DISP_ENQ_OPEN_REF))
210 ptlrpc_req_finished(it->it_request); /* ll_file_open */
212 if (it_disposition(it, DISP_ENQ_CREATE_REF)) /* create rec */
213 ptlrpc_req_finished(it->it_request);
215 it->it_disposition = 0;
216 it->it_request = NULL;
220 /* mark aliases invalid and prune unused aliases */
221 void ll_prune_aliases(struct inode *inode)
223 struct dentry *dentry;
226 LASSERT(inode != NULL);
228 CDEBUG(D_INODE, "marking dentries for inode "DFID"(%p) invalid\n",
229 PFID(ll_inode2fid(inode)), inode);
231 spin_lock(&inode->i_lock);
232 hlist_for_each_entry(dentry, &inode->i_dentry, d_alias)
233 d_lustre_invalidate(dentry);
234 spin_unlock(&inode->i_lock);
236 d_prune_aliases(inode);
241 int ll_revalidate_it_finish(struct ptlrpc_request *request,
242 struct lookup_intent *it,
251 if (it_disposition(it, DISP_LOOKUP_NEG))
254 rc = ll_prep_inode(&de->d_inode, request, NULL, it);
259 void ll_lookup_finish_locks(struct lookup_intent *it, struct dentry *dentry)
262 LASSERT(dentry != NULL);
264 if (it->it_lock_mode && dentry->d_inode != NULL) {
265 struct inode *inode = dentry->d_inode;
266 struct ll_sb_info *sbi = ll_i2sbi(dentry->d_inode);
268 CDEBUG(D_DLMTRACE, "setting l_data to inode "DFID"(%p)\n",
269 PFID(ll_inode2fid(inode)), inode);
270 ll_set_lock_data(sbi->ll_md_exp, inode, it, NULL);
273 /* drop lookup or getattr locks immediately */
274 if (it->it_op == IT_LOOKUP || it->it_op == IT_GETATTR) {
275 /* on 2.6 there are situation when several lookups and
276 * revalidations may be requested during single operation.
277 * therefore, we don't release intent here -bzzz */
278 ll_intent_drop_lock(it);
282 static int ll_revalidate_dentry(struct dentry *dentry,
283 unsigned int lookup_flags)
285 struct inode *dir = dentry->d_parent->d_inode;
287 CDEBUG(D_VFSTRACE, "VFS Op:name=%s, flags=%u\n",
288 dentry->d_name.name, lookup_flags);
290 /* If this is intermediate component path lookup and we were able to get
291 * to this dentry, then its lock has not been revoked and the
292 * path component is valid. */
293 if (lookup_flags & (LOOKUP_CONTINUE | LOOKUP_PARENT))
296 /* Symlink - always valid as long as the dentry was found */
297 /* only special case is to prevent ELOOP error from VFS during open
298 * of a foreign symlink file/dir with O_NOFOLLOW, like it happens for
299 * real symlinks. This will allow to open foreign symlink file/dir
300 * for get[dir]stripe/unlock ioctl()s.
302 #ifdef HAVE_IOP_GET_LINK
303 if (dentry->d_inode && dentry->d_inode->i_op->get_link) {
305 if (dentry->d_inode && dentry->d_inode->i_op->follow_link) {
307 if (!S_ISLNK(dentry->d_inode->i_mode) &&
308 !(lookup_flags & LOOKUP_FOLLOW))
315 * VFS warns us that this is the second go around and previous
316 * operation failed (most likely open|creat), so this time
317 * we better talk to the server via the lookup path by name,
320 if (lookup_flags & LOOKUP_REVAL)
323 if (lookup_flags & LOOKUP_RCU)
326 if (dentry_may_statahead(dir, dentry))
327 ll_revalidate_statahead(dir, &dentry, dentry->d_inode == NULL);
332 const struct dentry_operations ll_d_ops = {
333 .d_revalidate = ll_revalidate_dentry,
334 .d_release = ll_release,
335 .d_delete = ll_ddelete,
336 .d_compare = ll_dcompare,