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) 2008, 2010, Oracle and/or its affiliates. All rights reserved.
24 * Use is subject to license terms.
26 * Copyright (c) 2011, 2012, Intel Corporation.
29 * This file is part of Lustre, http://www.lustre.org/
30 * Lustre is a trademark of Sun Microsystems, Inc.
32 * glimpse code shared between vvp and liblustre (and other Lustre clients in
35 * Author: Nikita Danilov <nikita.danilov@sun.com>
36 * Author: Oleg Drokin <oleg.drokin@sun.com>
39 #include "../../include/linux/libcfs/libcfs.h"
40 #include "../include/obd_class.h"
41 #include "../include/obd_support.h"
42 #include "../include/obd.h"
44 #include "../include/lustre_dlm.h"
45 #include "../include/lustre_lite.h"
46 #include "../include/lustre_mdc.h"
47 #include <linux/pagemap.h>
48 #include <linux/file.h>
50 #include "../include/cl_object.h"
51 #include "../llite/llite_internal.h"
53 static const struct cl_lock_descr whole_file = {
55 .cld_end = CL_PAGE_EOF,
60 * Check whether file has possible unwriten pages.
62 * \retval 1 file is mmap-ed or has dirty pages
65 blkcnt_t dirty_cnt(struct inode *inode)
68 struct vvp_object *vob = cl_inode2vvp(inode);
72 cnt += radix_tree_gang_lookup_tag(&inode->i_mapping->page_tree,
75 if (cnt == 0 && atomic_read(&vob->vob_mmap_cnt) > 0)
78 return (cnt > 0) ? 1 : 0;
81 int cl_glimpse_lock(const struct lu_env *env, struct cl_io *io,
82 struct inode *inode, struct cl_object *clob, int agl)
84 struct ll_inode_info *lli = ll_i2info(inode);
85 const struct lu_fid *fid = lu_object_fid(&clob->co_lu);
89 if (!(lli->lli_flags & LLIF_MDS_SIZE_LOCK)) {
90 CDEBUG(D_DLMTRACE, "Glimpsing inode " DFID "\n", PFID(fid));
91 if (lli->lli_has_smd) {
92 struct cl_lock *lock = vvp_env_lock(env);
93 struct cl_lock_descr *descr = &lock->cll_descr;
95 /* NOTE: this looks like DLM lock request, but it may
96 * not be one. Due to CEF_ASYNC flag (translated
97 * to LDLM_FL_HAS_INTENT by osc), this is
98 * glimpse request, that won't revoke any
99 * conflicting DLM locks held. Instead,
100 * ll_glimpse_callback() will be called on each
101 * client holding a DLM lock against this file,
102 * and resulting size will be returned for each
103 * stripe. DLM lock on [0, EOF] is acquired only
104 * if there were no conflicting locks. If there
105 * were conflicting locks, enqueuing or waiting
106 * fails with -ENAVAIL, but valid inode
107 * attributes are returned anyway.
110 descr->cld_obj = clob;
111 descr->cld_mode = CLM_READ;
112 descr->cld_enq_flags = CEF_ASYNC | CEF_MUST;
114 descr->cld_enq_flags |= CEF_AGL;
116 * CEF_ASYNC is used because glimpse sub-locks cannot
117 * deadlock (because they never conflict with other
118 * locks) and, hence, can be enqueued out-of-order.
120 * CEF_MUST protects glimpse lock from conversion into
123 result = cl_lock_request(env, io, lock);
128 ll_merge_attr(env, inode);
129 if (i_size_read(inode) > 0 &&
130 inode->i_blocks == 0) {
132 * LU-417: Add dirty pages block count
133 * lest i_blocks reports 0, some "cp" or
134 * "tar" may think it's a completely
135 * sparse file and skip it.
137 inode->i_blocks = dirty_cnt(inode);
140 cl_lock_release(env, lock);
142 CDEBUG(D_DLMTRACE, "No objects for inode\n");
143 ll_merge_attr(env, inode);
150 static int cl_io_get(struct inode *inode, struct lu_env **envout,
151 struct cl_io **ioout, int *refcheck)
155 struct ll_inode_info *lli = ll_i2info(inode);
156 struct cl_object *clob = lli->lli_clob;
159 if (S_ISREG(inode->i_mode)) {
160 env = cl_env_get(refcheck);
162 io = vvp_env_thread_io(env);
168 result = PTR_ERR(env);
176 int cl_glimpse_size0(struct inode *inode, int agl)
179 * We don't need ast_flags argument to cl_glimpse_size(), because
180 * osc_lock_enqueue() takes care of the possible deadlock that said
181 * argument was introduced to avoid.
184 * XXX but note that ll_file_seek() passes LDLM_FL_BLOCK_NOWAIT to
185 * cl_glimpse_size(), which doesn't make sense: glimpse locks are not
188 struct lu_env *env = NULL;
189 struct cl_io *io = NULL;
193 result = cl_io_get(inode, &env, &io, &refcheck);
196 io->ci_verify_layout = 1;
197 result = cl_io_init(env, io, CIT_MISC, io->ci_obj);
200 * nothing to do for this io. This currently happens
201 * when stripe sub-object's are not yet created.
203 result = io->ci_result;
204 else if (result == 0)
205 result = cl_glimpse_lock(env, io, inode, io->ci_obj,
208 OBD_FAIL_TIMEOUT(OBD_FAIL_GLIMPSE_DELAY, 2);
210 if (unlikely(io->ci_need_restart))
212 cl_env_put(env, &refcheck);
217 int cl_local_size(struct inode *inode)
219 struct lu_env *env = NULL;
220 struct cl_io *io = NULL;
221 struct cl_object *clob;
225 if (!ll_i2info(inode)->lli_has_smd)
228 result = cl_io_get(inode, &env, &io, &refcheck);
233 result = cl_io_init(env, io, CIT_MISC, clob);
235 result = io->ci_result;
236 } else if (result == 0) {
237 struct cl_lock *lock = vvp_env_lock(env);
239 lock->cll_descr = whole_file;
240 lock->cll_descr.cld_enq_flags = CEF_PEEK;
241 lock->cll_descr.cld_obj = clob;
242 result = cl_lock_request(env, io, lock);
244 ll_merge_attr(env, inode);
245 cl_lock_release(env, lock);
249 cl_env_put(env, &refcheck);