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 2008 Sun Microsystems, Inc. All rights reserved.
30 * Use is subject to license terms.
33 * This file is part of Lustre, http://www.lustre.org/
34 * Lustre is a trademark of Sun Microsystems, Inc.
36 * Implementation of cl_page for LOV layer.
38 * Author: Nikita Danilov <nikita.danilov@sun.com>
41 #define DEBUG_SUBSYSTEM S_LOV
43 #include "lov_cl_internal.h"
45 /** \addtogroup lov lov @{ */
47 /*****************************************************************************
49 * Lov page operations.
53 static int lov_page_invariant(const struct cl_page_slice *slice)
55 const struct cl_page *page = slice->cpl_page;
56 const struct cl_page *sub = lov_sub_page(slice);
58 return ergo(sub != NULL,
59 page->cp_child == sub &&
60 sub->cp_parent == page &&
61 page->cp_state == sub->cp_state);
64 static void lov_page_fini(const struct lu_env *env,
65 struct cl_page_slice *slice)
67 struct lov_page *lp = cl2lov_page(slice);
68 struct cl_page *sub = lov_sub_page(slice);
70 LINVRNT(lov_page_invariant(slice));
74 LASSERT(sub->cp_state == CPS_FREEING);
75 lu_ref_del(&sub->cp_reference, "lov", sub->cp_parent);
76 sub->cp_parent = NULL;
77 slice->cpl_page->cp_child = NULL;
78 cl_page_put(env, sub);
80 OBD_SLAB_FREE_PTR(lp, lov_page_kmem);
84 static void lov_page_own(const struct lu_env *env,
85 const struct cl_page_slice *slice, struct cl_io *io)
87 struct lov_io *lio = lov_env_io(env);
88 struct lov_io_sub *sub;
90 LINVRNT(lov_page_invariant(slice));
91 LINVRNT(!cl2lov_page(slice)->lps_invalid);
94 sub = lov_page_subio(env, lio, slice);
96 lov_sub_page(slice)->cp_owner = sub->sub_io;
103 static void lov_page_assume(const struct lu_env *env,
104 const struct cl_page_slice *slice, struct cl_io *io)
106 return lov_page_own(env, slice, io);
109 static int lov_page_print(const struct lu_env *env,
110 const struct cl_page_slice *slice,
111 void *cookie, lu_printer_t printer)
113 struct lov_page *lp = cl2lov_page(slice);
115 return (*printer)(env, cookie, LUSTRE_LOV_NAME"-page@%p\n", lp);
118 static const struct cl_page_operations lov_page_ops = {
119 .cpo_fini = lov_page_fini,
120 .cpo_own = lov_page_own,
121 .cpo_assume = lov_page_assume,
122 .cpo_print = lov_page_print
125 static void lov_empty_page_fini(const struct lu_env *env,
126 struct cl_page_slice *slice)
128 struct lov_page *lp = cl2lov_page(slice);
130 LASSERT(slice->cpl_page->cp_child == NULL);
132 OBD_SLAB_FREE_PTR(lp, lov_page_kmem);
136 struct cl_page *lov_page_init_raid0(const struct lu_env *env,
137 struct cl_object *obj, struct cl_page *page,
140 struct lov_page *lpg;
141 struct lov_object *loo = cl2lov(obj);
145 OBD_SLAB_ALLOC_PTR(lpg, lov_page_kmem);
150 struct cl_page *subpage;
151 struct cl_object *subobj;
152 struct lov_layout_raid0 *r0 = lov_r0(loo);
154 offset = cl_offset(obj, page->cp_index);
155 stripe = lov_stripe_number(r0->lo_lsm, offset);
156 result = lov_stripe_offset(r0->lo_lsm, offset, stripe,
158 LASSERT(stripe < r0->lo_nr);
159 LASSERT(result == 0);
161 subobj = lovsub2cl(r0->lo_sub[stripe]);
162 subpage = cl_page_find(env, subobj,
163 cl_index(subobj, suboff), vmpage,
165 if (!IS_ERR(subpage)) {
166 if (subpage->cp_parent != NULL) {
168 * This is only possible when TRANSIENT page
169 * is being created, and CACHEABLE sub-page
170 * (attached to already existing top-page) has
171 * been found. Tell cl_page_find() to use
174 LASSERT(subpage->cp_type == CPT_CACHEABLE);
175 LASSERT(page->cp_type == CPT_TRANSIENT);
176 lpg->lps_invalid = 1;
177 cl_page_put(env, subpage);
179 * XXX This assumes that lov is in the topmost
182 result = PTR_ERR(cl_page_top(subpage));
184 lu_ref_add(&subpage->cp_reference, "lov", page);
185 subpage->cp_parent = page;
186 page->cp_child = subpage;
188 cl_page_slice_add(page, &lpg->lps_cl,
191 result = PTR_ERR(subpage);
194 RETURN(ERR_PTR(result));
198 static const struct cl_page_operations lov_empty_page_ops = {
199 .cpo_fini = lov_empty_page_fini,
200 .cpo_print = lov_page_print
203 struct cl_page *lov_page_init_empty(const struct lu_env *env,
204 struct cl_object *obj, struct cl_page *page,
207 struct lov_page *lpg;
208 int result = -ENOMEM;
211 OBD_SLAB_ALLOC_PTR(lpg, lov_page_kmem);
214 cl_page_slice_add(page, &lpg->lps_cl,
215 obj, &lov_empty_page_ops);
216 addr = cfs_kmap(vmpage);
217 memset(addr, 0, cl_page_size(obj));
219 cl_page_export(env, page);
222 RETURN(ERR_PTR(result));