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, 2017, Intel Corporation.
29 * This file is part of Lustre, http://www.lustre.org/
30 * Lustre is a trademark of Sun Microsystems, Inc.
32 * Implementation of cl_page for LOV layer.
34 * Author: Nikita Danilov <nikita.danilov@sun.com>
35 * Author: Jinshan Xiong <jinshan.xiong@intel.com>
38 #define DEBUG_SUBSYSTEM S_LOV
40 #include "lov_cl_internal.h"
46 /*****************************************************************************
48 * Lov page operations.
52 static int lov_comp_page_print(const struct lu_env *env,
53 const struct cl_page_slice *slice,
54 void *cookie, lu_printer_t printer)
56 struct lov_page *lp = cl2lov_page(slice);
58 return (*printer)(env, cookie,
59 LUSTRE_LOV_NAME"-page@%p, gen: %u\n",
60 lp, lp->lps_layout_gen);
63 static const struct cl_page_operations lov_comp_page_ops = {
64 .cpo_print = lov_comp_page_print
67 int lov_page_init_composite(const struct lu_env *env, struct cl_object *obj,
68 struct cl_page *page, pgoff_t index)
70 struct lov_object *loo = cl2lov(obj);
71 struct lov_io *lio = lov_env_io(env);
72 struct cl_object *subobj;
74 struct lov_io_sub *sub;
75 struct lov_page *lpg = cl_object_page_slice(obj, page);
76 struct lov_layout_raid0 *r0;
85 offset = cl_offset(obj, index);
86 entry = lov_io_layout_at(lio, offset);
87 if (entry < 0 || !lsm_entry_inited(loo->lo_lsm, entry)) {
88 /* non-existing layout component */
89 lov_page_init_empty(env, obj, page, index);
93 r0 = lov_r0(loo, entry);
94 stripe = lov_stripe_number(loo->lo_lsm, entry, offset);
95 LASSERT(stripe < r0->lo_nr);
96 rc = lov_stripe_offset(loo->lo_lsm, entry, offset, stripe, &suboff);
99 page->cp_lov_index = lov_comp_index(entry, stripe);
100 lpg->lps_layout_gen = loo->lo_lsm->lsm_layout_gen;
101 cl_page_slice_add(page, &lpg->lps_cl, obj, index, &lov_comp_page_ops);
103 sub = lov_sub_get(env, lio, page->cp_lov_index);
105 RETURN(PTR_ERR(sub));
107 subobj = lovsub2cl(r0->lo_sub[stripe]);
108 list_for_each_entry(o, &subobj->co_lu.lo_header->loh_layers,
110 if (o->co_ops->coo_page_init) {
111 rc = o->co_ops->coo_page_init(sub->sub_env, o, page,
112 cl_index(subobj, suboff));
121 static int lov_empty_page_print(const struct lu_env *env,
122 const struct cl_page_slice *slice,
123 void *cookie, lu_printer_t printer)
125 struct lov_page *lp = cl2lov_page(slice);
127 return (*printer)(env, cookie, LUSTRE_LOV_NAME"-page@%p, empty.\n", lp);
130 static const struct cl_page_operations lov_empty_page_ops = {
131 .cpo_print = lov_empty_page_print
134 int lov_page_init_empty(const struct lu_env *env, struct cl_object *obj,
135 struct cl_page *page, pgoff_t index)
137 struct lov_page *lpg = cl_object_page_slice(obj, page);
142 page->cp_lov_index = ~0;
143 cl_page_slice_add(page, &lpg->lps_cl, obj, index, &lov_empty_page_ops);
144 addr = kmap(page->cp_vmpage);
145 memset(addr, 0, cl_page_size(obj));
146 kunmap(page->cp_vmpage);
147 cl_page_export(env, page, 1);
151 int lov_page_init_foreign(const struct lu_env *env, struct cl_object *obj,
152 struct cl_page *page, pgoff_t index)
154 CDEBUG(D_PAGE, DFID" has no data\n", PFID(lu_object_fid(&obj->co_lu)));
158 bool lov_page_is_empty(const struct cl_page *page)
160 const struct cl_page_slice *slice = cl_page_at(page, &lov_device_type);
162 LASSERT(slice != NULL);
163 return slice->cpl_ops == &lov_empty_page_ops;