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) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
30 * Use is subject to license terms.
32 * Copyright (c) 2011, 2012, Whamcloud, Inc.
35 * This file is part of Lustre, http://www.lustre.org/
36 * Lustre is a trademark of Sun Microsystems, Inc.
38 * glimpse code shared between vvp and liblustre (and other Lustre clients in
41 * Author: Nikita Danilov <nikita.danilov@sun.com>
42 * Author: Oleg Drokin <oleg.drokin@sun.com>
45 #include <libcfs/libcfs.h>
46 #include <obd_class.h>
47 #include <obd_support.h>
51 # include <lustre_dlm.h>
52 # include <lustre_lite.h>
53 # include <lustre_mdc.h>
54 # include <linux/pagemap.h>
55 # include <linux/file.h>
61 #include <sys/types.h>
63 #include <sys/queue.h>
65 #include <liblustre.h>
68 #include "cl_object.h"
71 # include "../llite/llite_internal.h"
73 # include "../liblustre/llite_lib.h"
76 static const struct cl_lock_descr whole_file = {
78 .cld_end = CL_PAGE_EOF,
83 * Check whether file has possible unwriten pages.
85 * \retval 1 file is mmap-ed or has dirty pages
88 blkcnt_t dirty_cnt(struct inode *inode)
92 struct ccc_object *vob = cl_inode2ccc(inode);
95 if (inode->i_mapping != NULL)
96 cnt += radix_tree_gang_lookup_tag(&inode->i_mapping->page_tree,
99 if (cnt == 0 && cfs_atomic_read(&vob->cob_mmap_cnt) > 0)
103 return (cnt > 0) ? 1 : 0;
106 int cl_glimpse_lock(const struct lu_env *env, struct cl_io *io,
107 struct inode *inode, struct cl_object *clob, int agl)
109 struct cl_lock_descr *descr = &ccc_env_info(env)->cti_descr;
110 struct cl_inode_info *lli = cl_i2info(inode);
111 const struct lu_fid *fid = lu_object_fid(&clob->co_lu);
112 struct ccc_io *cio = ccc_env_io(env);
113 struct cl_lock *lock;
118 if (!(lli->lli_flags & LLIF_MDS_SIZE_LOCK)) {
119 CDEBUG(D_DLMTRACE, "Glimpsing inode "DFID"\n", PFID(fid));
121 /* NOTE: this looks like DLM lock request, but it may
122 * not be one. Due to CEF_ASYNC flag (translated
123 * to LDLM_FL_HAS_INTENT by osc), this is
124 * glimpse request, that won't revoke any
125 * conflicting DLM locks held. Instead,
126 * ll_glimpse_callback() will be called on each
127 * client holding a DLM lock against this file,
128 * and resulting size will be returned for each
129 * stripe. DLM lock on [0, EOF] is acquired only
130 * if there were no conflicting locks. If there
131 * were conflicting locks, enqueuing or waiting
132 * fails with -ENAVAIL, but valid inode
133 * attributes are returned anyway. */
135 descr->cld_obj = clob;
136 descr->cld_mode = CLM_PHANTOM;
137 descr->cld_enq_flags = CEF_ASYNC | CEF_MUST;
139 descr->cld_enq_flags |= CEF_AGL;
140 cio->cui_glimpse = 1;
142 * CEF_ASYNC is used because glimpse sub-locks cannot
143 * deadlock (because they never conflict with other
144 * locks) and, hence, can be enqueued out-of-order.
146 * CEF_MUST protects glimpse lock from conversion into
149 lock = cl_lock_request(env, io, descr, "glimpse",
151 cio->cui_glimpse = 0;
157 RETURN(PTR_ERR(lock));
160 result = cl_wait(env, lock);
163 if (cl_isize_read(inode) > 0 &&
164 inode->i_blocks == 0) {
166 * LU-417: Add dirty pages block count
167 * lest i_blocks reports 0, some "cp" or
168 * "tar" may think it's a completely
169 * sparse file and skip it.
171 inode->i_blocks = dirty_cnt(inode);
175 cl_lock_release(env, lock, "glimpse", cfs_current());
177 CDEBUG(D_DLMTRACE, "No objects for inode\n");
184 static int cl_io_get(struct inode *inode, struct lu_env **envout,
185 struct cl_io **ioout, int *refcheck)
189 struct cl_inode_info *lli = cl_i2info(inode);
190 struct cl_object *clob = lli->lli_clob;
193 if (S_ISREG(cl_inode_mode(inode))) {
194 env = cl_env_get(refcheck);
196 io = ccc_env_thread_io(env);
202 result = PTR_ERR(env);
208 int cl_glimpse_size0(struct inode *inode, int agl)
211 * We don't need ast_flags argument to cl_glimpse_size(), because
212 * osc_lock_enqueue() takes care of the possible deadlock that said
213 * argument was introduced to avoid.
216 * XXX but note that ll_file_seek() passes LDLM_FL_BLOCK_NOWAIT to
217 * cl_glimpse_size(), which doesn't make sense: glimpse locks are not
220 struct lu_env *env = NULL;
221 struct cl_io *io = NULL;
227 result = cl_io_get(inode, &env, &io, &refcheck);
229 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
232 * nothing to do for this io. This currently happens
233 * when stripe sub-object's are not yet created.
235 result = io->ci_result;
236 else if (result == 0)
237 result = cl_glimpse_lock(env, io, inode, io->ci_obj,
240 cl_env_put(env, &refcheck);
245 int cl_local_size(struct inode *inode)
247 struct lu_env *env = NULL;
248 struct cl_io *io = NULL;
249 struct ccc_thread_info *cti;
250 struct cl_object *clob;
251 struct cl_lock_descr *descr;
252 struct cl_lock *lock;
258 if (!cl_i2info(inode)->lli_smd)
261 result = cl_io_get(inode, &env, &io, &refcheck);
266 result = cl_io_init(env, io, CIT_MISC, clob);
268 result = io->ci_result;
269 else if (result == 0) {
270 cti = ccc_env_info(env);
271 descr = &cti->cti_descr;
274 descr->cld_obj = clob;
275 lock = cl_lock_peek(env, io, descr, "localsize", cfs_current());
279 cl_lock_release(env, lock, "localsize", cfs_current());
285 cl_env_put(env, &refcheck);