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 Whamcloud, Inc.
36 * This file is part of Lustre, http://www.lustre.org/
37 * Lustre is a trademark of Sun Microsystems, Inc.
39 * glimpse code shared between vvp and liblustre (and other Lustre clients in
42 * Author: Nikita Danilov <nikita.danilov@sun.com>
43 * Author: Oleg Drokin <oleg.drokin@sun.com>
46 #include <libcfs/libcfs.h>
47 #include <obd_class.h>
48 #include <obd_support.h>
52 # include <lustre_dlm.h>
53 # include <lustre_lite.h>
54 # include <lustre_mdc.h>
55 # include <linux/pagemap.h>
56 # include <linux/file.h>
62 #include <sys/types.h>
64 #include <sys/queue.h>
66 #include <liblustre.h>
69 #include "cl_object.h"
72 # include "../llite/llite_internal.h"
74 # include "../liblustre/llite_lib.h"
77 static const struct cl_lock_descr whole_file = {
79 .cld_end = CL_PAGE_EOF,
84 * Check whether file has possible unwriten pages.
86 * \retval 1 file is mmap-ed or has dirty pages
89 blkcnt_t dirty_cnt(struct inode *inode)
93 struct ccc_object *vob = cl_inode2ccc(inode);
96 if (inode->i_mapping != NULL)
97 cnt += radix_tree_gang_lookup_tag(&inode->i_mapping->page_tree,
100 if (cnt == 0 && cfs_atomic_read(&vob->cob_mmap_cnt) > 0)
104 return (cnt > 0) ? 1 : 0;
107 int cl_glimpse_lock(const struct lu_env *env, struct cl_io *io,
108 struct inode *inode, struct cl_object *clob, int agl)
110 struct cl_lock_descr *descr = &ccc_env_info(env)->cti_descr;
111 struct cl_inode_info *lli = cl_i2info(inode);
112 const struct lu_fid *fid = lu_object_fid(&clob->co_lu);
113 struct ccc_io *cio = ccc_env_io(env);
114 struct cl_lock *lock;
119 if (!(lli->lli_flags & LLIF_MDS_SIZE_LOCK)) {
120 CDEBUG(D_DLMTRACE, "Glimpsing inode "DFID"\n", PFID(fid));
122 /* NOTE: this looks like DLM lock request, but it may
123 * not be one. Due to CEF_ASYNC flag (translated
124 * to LDLM_FL_HAS_INTENT by osc), this is
125 * glimpse request, that won't revoke any
126 * conflicting DLM locks held. Instead,
127 * ll_glimpse_callback() will be called on each
128 * client holding a DLM lock against this file,
129 * and resulting size will be returned for each
130 * stripe. DLM lock on [0, EOF] is acquired only
131 * if there were no conflicting locks. If there
132 * were conflicting locks, enqueuing or waiting
133 * fails with -ENAVAIL, but valid inode
134 * attributes are returned anyway. */
136 descr->cld_obj = clob;
137 descr->cld_mode = CLM_PHANTOM;
138 descr->cld_enq_flags = CEF_ASYNC | CEF_MUST;
140 descr->cld_enq_flags |= CEF_AGL;
141 cio->cui_glimpse = 1;
143 * CEF_ASYNC is used because glimpse sub-locks cannot
144 * deadlock (because they never conflict with other
145 * locks) and, hence, can be enqueued out-of-order.
147 * CEF_MUST protects glimpse lock from conversion into
150 lock = cl_lock_request(env, io, descr, "glimpse",
152 cio->cui_glimpse = 0;
158 RETURN(PTR_ERR(lock));
161 result = cl_wait(env, lock);
164 if (cl_isize_read(inode) > 0 &&
165 inode->i_blocks == 0) {
167 * LU-417: Add dirty pages block count
168 * lest i_blocks reports 0, some "cp" or
169 * "tar" may think it's a completely
170 * sparse file and skip it.
172 inode->i_blocks = dirty_cnt(inode);
176 cl_lock_release(env, lock, "glimpse", cfs_current());
178 CDEBUG(D_DLMTRACE, "No objects for inode\n");
185 static int cl_io_get(struct inode *inode, struct lu_env **envout,
186 struct cl_io **ioout, int *refcheck)
190 struct cl_inode_info *lli = cl_i2info(inode);
191 struct cl_object *clob = lli->lli_clob;
194 if (S_ISREG(cl_inode_mode(inode))) {
195 env = cl_env_get(refcheck);
197 io = ccc_env_thread_io(env);
203 result = PTR_ERR(env);
209 int cl_glimpse_size0(struct inode *inode, int agl)
212 * We don't need ast_flags argument to cl_glimpse_size(), because
213 * osc_lock_enqueue() takes care of the possible deadlock that said
214 * argument was introduced to avoid.
217 * XXX but note that ll_file_seek() passes LDLM_FL_BLOCK_NOWAIT to
218 * cl_glimpse_size(), which doesn't make sense: glimpse locks are not
221 struct lu_env *env = NULL;
222 struct cl_io *io = NULL;
228 result = cl_io_get(inode, &env, &io, &refcheck);
230 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
233 * nothing to do for this io. This currently happens
234 * when stripe sub-object's are not yet created.
236 result = io->ci_result;
237 else if (result == 0)
238 result = cl_glimpse_lock(env, io, inode, io->ci_obj,
241 cl_env_put(env, &refcheck);
246 int cl_local_size(struct inode *inode)
248 struct lu_env *env = NULL;
249 struct cl_io *io = NULL;
250 struct ccc_thread_info *cti;
251 struct cl_object *clob;
252 struct cl_lock_descr *descr;
253 struct cl_lock *lock;
259 if (!cl_i2info(inode)->lli_smd)
262 result = cl_io_get(inode, &env, &io, &refcheck);
267 result = cl_io_init(env, io, CIT_MISC, clob);
269 result = io->ci_result;
270 else if (result == 0) {
271 cti = ccc_env_info(env);
272 descr = &cti->cti_descr;
275 descr->cld_obj = clob;
276 lock = cl_lock_peek(env, io, descr, "localsize", cfs_current());
280 cl_lock_release(env, lock, "localsize", cfs_current());
286 cl_env_put(env, &refcheck);