blob: 52eaf33d346fd5bdd0b5a9ee5e201f514c03aca5 [file] [log] [blame]
Mark Fashehccd979b2005-12-15 14:31:24 -08001/* -*- mode: c; c-basic-offset: 8; -*-
2 * vim: noexpandtab sw=8 ts=8 sts=0:
3 *
4 * uptodate.c
5 *
6 * Tracking the up-to-date-ness of a local buffer_head with respect to
7 * the cluster.
8 *
9 * Copyright (C) 2002, 2004, 2005 Oracle. All rights reserved.
10 *
11 * This program is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU General Public
13 * License as published by the Free Software Foundation; either
14 * version 2 of the License, or (at your option) any later version.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
19 * General Public License for more details.
20 *
21 * You should have received a copy of the GNU General Public
22 * License along with this program; if not, write to the
23 * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
24 * Boston, MA 021110-1307, USA.
25 *
26 * Standard buffer head caching flags (uptodate, etc) are insufficient
27 * in a clustered environment - a buffer may be marked up to date on
28 * our local node but could have been modified by another cluster
29 * member. As a result an additional (and performant) caching scheme
30 * is required. A further requirement is that we consume as little
31 * memory as possible - we never pin buffer_head structures in order
32 * to cache them.
33 *
34 * We track the existence of up to date buffers on the inodes which
35 * are associated with them. Because we don't want to pin
36 * buffer_heads, this is only a (strong) hint and several other checks
37 * are made in the I/O path to ensure that we don't use a stale or
38 * invalid buffer without going to disk:
39 * - buffer_jbd is used liberally - if a bh is in the journal on
40 * this node then it *must* be up to date.
41 * - the standard buffer_uptodate() macro is used to detect buffers
42 * which may be invalid (even if we have an up to date tracking
43 * item for them)
44 *
45 * For a full understanding of how this code works together, one
46 * should read the callers in dlmglue.c, the I/O functions in
47 * buffer_head_io.c and ocfs2_journal_access in journal.c
48 */
49
50#include <linux/fs.h>
51#include <linux/types.h>
52#include <linux/slab.h>
53#include <linux/highmem.h>
54#include <linux/buffer_head.h>
55#include <linux/rbtree.h>
Mark Fashehccd979b2005-12-15 14:31:24 -080056
Mark Fashehccd979b2005-12-15 14:31:24 -080057#include <cluster/masklog.h>
58
59#include "ocfs2.h"
60
61#include "inode.h"
62#include "uptodate.h"
Tao Mad7014852011-02-24 16:22:20 +080063#include "ocfs2_trace.h"
Mark Fashehccd979b2005-12-15 14:31:24 -080064
65struct ocfs2_meta_cache_item {
66 struct rb_node c_node;
67 sector_t c_block;
68};
69
Christoph Lametere18b8902006-12-06 20:33:20 -080070static struct kmem_cache *ocfs2_uptodate_cachep = NULL;
Mark Fashehccd979b2005-12-15 14:31:24 -080071
Joel Becker8cb471e2009-02-10 20:00:41 -080072u64 ocfs2_metadata_cache_owner(struct ocfs2_caching_info *ci)
Mark Fashehccd979b2005-12-15 14:31:24 -080073{
Joel Becker6e5a3d72009-02-10 19:00:37 -080074 BUG_ON(!ci || !ci->ci_ops);
75
76 return ci->ci_ops->co_owner(ci);
77}
78
Joel Becker8cb471e2009-02-10 20:00:41 -080079struct super_block *ocfs2_metadata_cache_get_super(struct ocfs2_caching_info *ci)
80{
81 BUG_ON(!ci || !ci->ci_ops);
82
83 return ci->ci_ops->co_get_super(ci);
84}
85
Joel Becker6e5a3d72009-02-10 19:00:37 -080086static void ocfs2_metadata_cache_lock(struct ocfs2_caching_info *ci)
87{
88 BUG_ON(!ci || !ci->ci_ops);
89
90 ci->ci_ops->co_cache_lock(ci);
91}
92
93static void ocfs2_metadata_cache_unlock(struct ocfs2_caching_info *ci)
94{
95 BUG_ON(!ci || !ci->ci_ops);
96
97 ci->ci_ops->co_cache_unlock(ci);
98}
99
Joel Becker8cb471e2009-02-10 20:00:41 -0800100void ocfs2_metadata_cache_io_lock(struct ocfs2_caching_info *ci)
Joel Becker6e5a3d72009-02-10 19:00:37 -0800101{
102 BUG_ON(!ci || !ci->ci_ops);
103
104 ci->ci_ops->co_io_lock(ci);
105}
106
Joel Becker8cb471e2009-02-10 20:00:41 -0800107void ocfs2_metadata_cache_io_unlock(struct ocfs2_caching_info *ci)
Joel Becker6e5a3d72009-02-10 19:00:37 -0800108{
109 BUG_ON(!ci || !ci->ci_ops);
110
111 ci->ci_ops->co_io_unlock(ci);
112}
113
114
Joel Becker66fb3452009-02-12 15:24:40 -0800115static void ocfs2_metadata_cache_reset(struct ocfs2_caching_info *ci,
116 int clear)
117{
118 ci->ci_flags |= OCFS2_CACHE_FL_INLINE;
119 ci->ci_num_cached = 0;
120
Joel Becker292dd272009-02-12 15:41:59 -0800121 if (clear) {
122 ci->ci_created_trans = 0;
Joel Becker66fb3452009-02-12 15:24:40 -0800123 ci->ci_last_trans = 0;
Joel Becker292dd272009-02-12 15:41:59 -0800124 }
Joel Becker66fb3452009-02-12 15:24:40 -0800125}
126
Joel Becker6e5a3d72009-02-10 19:00:37 -0800127void ocfs2_metadata_cache_init(struct ocfs2_caching_info *ci,
128 const struct ocfs2_caching_operations *ops)
129{
130 BUG_ON(!ops);
131
132 ci->ci_ops = ops;
Joel Becker66fb3452009-02-12 15:24:40 -0800133 ocfs2_metadata_cache_reset(ci, 1);
Mark Fashehccd979b2005-12-15 14:31:24 -0800134}
135
Joel Becker66fb3452009-02-12 15:24:40 -0800136void ocfs2_metadata_cache_exit(struct ocfs2_caching_info *ci)
137{
138 ocfs2_metadata_cache_purge(ci);
139 ocfs2_metadata_cache_reset(ci, 1);
140}
141
142
Mark Fashehccd979b2005-12-15 14:31:24 -0800143/* No lock taken here as 'root' is not expected to be visible to other
144 * processes. */
145static unsigned int ocfs2_purge_copied_metadata_tree(struct rb_root *root)
146{
147 unsigned int purged = 0;
148 struct rb_node *node;
149 struct ocfs2_meta_cache_item *item;
150
151 while ((node = rb_last(root)) != NULL) {
152 item = rb_entry(node, struct ocfs2_meta_cache_item, c_node);
153
Tao Mad7014852011-02-24 16:22:20 +0800154 trace_ocfs2_purge_copied_metadata_tree(
155 (unsigned long long) item->c_block);
Mark Fashehccd979b2005-12-15 14:31:24 -0800156
157 rb_erase(&item->c_node, root);
158 kmem_cache_free(ocfs2_uptodate_cachep, item);
159
160 purged++;
161 }
162 return purged;
163}
164
165/* Called from locking and called from ocfs2_clear_inode. Dump the
166 * cache for a given inode.
167 *
168 * This function is a few more lines longer than necessary due to some
169 * accounting done here, but I think it's worth tracking down those
170 * bugs sooner -- Mark */
Joel Becker8cb471e2009-02-10 20:00:41 -0800171void ocfs2_metadata_cache_purge(struct ocfs2_caching_info *ci)
Mark Fashehccd979b2005-12-15 14:31:24 -0800172{
Mark Fashehccd979b2005-12-15 14:31:24 -0800173 unsigned int tree, to_purge, purged;
Mark Fashehccd979b2005-12-15 14:31:24 -0800174 struct rb_root root = RB_ROOT;
175
Joel Becker6e5a3d72009-02-10 19:00:37 -0800176 BUG_ON(!ci || !ci->ci_ops);
177
178 ocfs2_metadata_cache_lock(ci);
Joel Becker47460d62009-02-10 16:05:07 -0800179 tree = !(ci->ci_flags & OCFS2_CACHE_FL_INLINE);
Mark Fashehccd979b2005-12-15 14:31:24 -0800180 to_purge = ci->ci_num_cached;
181
Tao Mad7014852011-02-24 16:22:20 +0800182 trace_ocfs2_metadata_cache_purge(
183 (unsigned long long)ocfs2_metadata_cache_owner(ci),
184 to_purge, tree);
Mark Fashehccd979b2005-12-15 14:31:24 -0800185
186 /* If we're a tree, save off the root so that we can safely
187 * initialize the cache. We do the work to free tree members
188 * without the spinlock. */
189 if (tree)
190 root = ci->ci_cache.ci_tree;
191
Joel Becker66fb3452009-02-12 15:24:40 -0800192 ocfs2_metadata_cache_reset(ci, 0);
Joel Becker6e5a3d72009-02-10 19:00:37 -0800193 ocfs2_metadata_cache_unlock(ci);
Mark Fashehccd979b2005-12-15 14:31:24 -0800194
195 purged = ocfs2_purge_copied_metadata_tree(&root);
196 /* If possible, track the number wiped so that we can more
197 * easily detect counting errors. Unfortunately, this is only
198 * meaningful for trees. */
199 if (tree && purged != to_purge)
Joel Becker6e5a3d72009-02-10 19:00:37 -0800200 mlog(ML_ERROR, "Owner %llu, count = %u, purged = %u\n",
201 (unsigned long long)ocfs2_metadata_cache_owner(ci),
202 to_purge, purged);
Mark Fashehccd979b2005-12-15 14:31:24 -0800203}
204
205/* Returns the index in the cache array, -1 if not found.
206 * Requires ip_lock. */
207static int ocfs2_search_cache_array(struct ocfs2_caching_info *ci,
208 sector_t item)
209{
210 int i;
211
212 for (i = 0; i < ci->ci_num_cached; i++) {
213 if (item == ci->ci_cache.ci_array[i])
214 return i;
215 }
216
217 return -1;
218}
219
220/* Returns the cache item if found, otherwise NULL.
221 * Requires ip_lock. */
222static struct ocfs2_meta_cache_item *
223ocfs2_search_cache_tree(struct ocfs2_caching_info *ci,
224 sector_t block)
225{
226 struct rb_node * n = ci->ci_cache.ci_tree.rb_node;
227 struct ocfs2_meta_cache_item *item = NULL;
228
229 while (n) {
230 item = rb_entry(n, struct ocfs2_meta_cache_item, c_node);
231
232 if (block < item->c_block)
233 n = n->rb_left;
234 else if (block > item->c_block)
235 n = n->rb_right;
236 else
237 return item;
238 }
239
240 return NULL;
241}
242
Joel Becker8cb471e2009-02-10 20:00:41 -0800243static int ocfs2_buffer_cached(struct ocfs2_caching_info *ci,
Mark Fashehccd979b2005-12-15 14:31:24 -0800244 struct buffer_head *bh)
245{
246 int index = -1;
247 struct ocfs2_meta_cache_item *item = NULL;
248
Joel Becker6e5a3d72009-02-10 19:00:37 -0800249 ocfs2_metadata_cache_lock(ci);
Mark Fashehccd979b2005-12-15 14:31:24 -0800250
Tao Mad7014852011-02-24 16:22:20 +0800251 trace_ocfs2_buffer_cached_begin(
252 (unsigned long long)ocfs2_metadata_cache_owner(ci),
253 (unsigned long long) bh->b_blocknr,
254 !!(ci->ci_flags & OCFS2_CACHE_FL_INLINE));
Mark Fashehccd979b2005-12-15 14:31:24 -0800255
Joel Becker47460d62009-02-10 16:05:07 -0800256 if (ci->ci_flags & OCFS2_CACHE_FL_INLINE)
Joel Becker8cb471e2009-02-10 20:00:41 -0800257 index = ocfs2_search_cache_array(ci, bh->b_blocknr);
Mark Fashehccd979b2005-12-15 14:31:24 -0800258 else
Joel Becker8cb471e2009-02-10 20:00:41 -0800259 item = ocfs2_search_cache_tree(ci, bh->b_blocknr);
Mark Fashehccd979b2005-12-15 14:31:24 -0800260
Joel Becker6e5a3d72009-02-10 19:00:37 -0800261 ocfs2_metadata_cache_unlock(ci);
Mark Fashehccd979b2005-12-15 14:31:24 -0800262
Tao Mad7014852011-02-24 16:22:20 +0800263 trace_ocfs2_buffer_cached_end(index, item);
Mark Fashehccd979b2005-12-15 14:31:24 -0800264
265 return (index != -1) || (item != NULL);
266}
267
268/* Warning: even if it returns true, this does *not* guarantee that
Sunil Mushran2bd63212010-01-25 16:57:38 -0800269 * the block is stored in our inode metadata cache.
270 *
Mark Fashehaa958872006-04-21 13:49:02 -0700271 * This can be called under lock_buffer()
272 */
Joel Becker8cb471e2009-02-10 20:00:41 -0800273int ocfs2_buffer_uptodate(struct ocfs2_caching_info *ci,
Mark Fashehccd979b2005-12-15 14:31:24 -0800274 struct buffer_head *bh)
275{
276 /* Doesn't matter if the bh is in our cache or not -- if it's
277 * not marked uptodate then we know it can't have correct
278 * data. */
279 if (!buffer_uptodate(bh))
280 return 0;
281
282 /* OCFS2 does not allow multiple nodes to be changing the same
283 * block at the same time. */
284 if (buffer_jbd(bh))
285 return 1;
286
287 /* Ok, locally the buffer is marked as up to date, now search
288 * our cache to see if we can trust that. */
Joel Becker8cb471e2009-02-10 20:00:41 -0800289 return ocfs2_buffer_cached(ci, bh);
Mark Fashehccd979b2005-12-15 14:31:24 -0800290}
291
Joel Becker8cb471e2009-02-10 20:00:41 -0800292/*
Mark Fashehaa958872006-04-21 13:49:02 -0700293 * Determine whether a buffer is currently out on a read-ahead request.
Joel Becker47460d62009-02-10 16:05:07 -0800294 * ci_io_sem should be held to serialize submitters with the logic here.
Mark Fashehaa958872006-04-21 13:49:02 -0700295 */
Joel Becker8cb471e2009-02-10 20:00:41 -0800296int ocfs2_buffer_read_ahead(struct ocfs2_caching_info *ci,
Mark Fashehaa958872006-04-21 13:49:02 -0700297 struct buffer_head *bh)
298{
Joel Becker8cb471e2009-02-10 20:00:41 -0800299 return buffer_locked(bh) && ocfs2_buffer_cached(ci, bh);
Mark Fashehaa958872006-04-21 13:49:02 -0700300}
301
Mark Fashehccd979b2005-12-15 14:31:24 -0800302/* Requires ip_lock */
303static void ocfs2_append_cache_array(struct ocfs2_caching_info *ci,
304 sector_t block)
305{
Joel Becker47460d62009-02-10 16:05:07 -0800306 BUG_ON(ci->ci_num_cached >= OCFS2_CACHE_INFO_MAX_ARRAY);
Mark Fashehccd979b2005-12-15 14:31:24 -0800307
Tao Mad7014852011-02-24 16:22:20 +0800308 trace_ocfs2_append_cache_array(
309 (unsigned long long)ocfs2_metadata_cache_owner(ci),
310 (unsigned long long)block, ci->ci_num_cached);
Mark Fashehccd979b2005-12-15 14:31:24 -0800311
312 ci->ci_cache.ci_array[ci->ci_num_cached] = block;
313 ci->ci_num_cached++;
314}
315
316/* By now the caller should have checked that the item does *not*
317 * exist in the tree.
318 * Requires ip_lock. */
319static void __ocfs2_insert_cache_tree(struct ocfs2_caching_info *ci,
320 struct ocfs2_meta_cache_item *new)
321{
322 sector_t block = new->c_block;
323 struct rb_node *parent = NULL;
324 struct rb_node **p = &ci->ci_cache.ci_tree.rb_node;
325 struct ocfs2_meta_cache_item *tmp;
326
Tao Mad7014852011-02-24 16:22:20 +0800327 trace_ocfs2_insert_cache_tree(
328 (unsigned long long)ocfs2_metadata_cache_owner(ci),
329 (unsigned long long)block, ci->ci_num_cached);
Mark Fashehccd979b2005-12-15 14:31:24 -0800330
331 while(*p) {
332 parent = *p;
333
334 tmp = rb_entry(parent, struct ocfs2_meta_cache_item, c_node);
335
336 if (block < tmp->c_block)
337 p = &(*p)->rb_left;
338 else if (block > tmp->c_block)
339 p = &(*p)->rb_right;
340 else {
341 /* This should never happen! */
342 mlog(ML_ERROR, "Duplicate block %llu cached!\n",
343 (unsigned long long) block);
344 BUG();
345 }
346 }
347
348 rb_link_node(&new->c_node, parent, p);
349 rb_insert_color(&new->c_node, &ci->ci_cache.ci_tree);
350 ci->ci_num_cached++;
351}
352
Joel Becker6e5a3d72009-02-10 19:00:37 -0800353/* co_cache_lock() must be held */
Joel Becker8cb471e2009-02-10 20:00:41 -0800354static inline int ocfs2_insert_can_use_array(struct ocfs2_caching_info *ci)
Mark Fashehccd979b2005-12-15 14:31:24 -0800355{
Joel Becker47460d62009-02-10 16:05:07 -0800356 return (ci->ci_flags & OCFS2_CACHE_FL_INLINE) &&
357 (ci->ci_num_cached < OCFS2_CACHE_INFO_MAX_ARRAY);
Mark Fashehccd979b2005-12-15 14:31:24 -0800358}
359
Joel Becker47460d62009-02-10 16:05:07 -0800360/* tree should be exactly OCFS2_CACHE_INFO_MAX_ARRAY wide. NULL the
Mark Fashehccd979b2005-12-15 14:31:24 -0800361 * pointers in tree after we use them - this allows caller to detect
Joel Becker6e5a3d72009-02-10 19:00:37 -0800362 * when to free in case of error.
363 *
364 * The co_cache_lock() must be held. */
Joel Becker8cb471e2009-02-10 20:00:41 -0800365static void ocfs2_expand_cache(struct ocfs2_caching_info *ci,
Mark Fashehccd979b2005-12-15 14:31:24 -0800366 struct ocfs2_meta_cache_item **tree)
367{
368 int i;
Mark Fashehccd979b2005-12-15 14:31:24 -0800369
Joel Becker47460d62009-02-10 16:05:07 -0800370 mlog_bug_on_msg(ci->ci_num_cached != OCFS2_CACHE_INFO_MAX_ARRAY,
Joel Becker6e5a3d72009-02-10 19:00:37 -0800371 "Owner %llu, num cached = %u, should be %u\n",
372 (unsigned long long)ocfs2_metadata_cache_owner(ci),
373 ci->ci_num_cached, OCFS2_CACHE_INFO_MAX_ARRAY);
Joel Becker47460d62009-02-10 16:05:07 -0800374 mlog_bug_on_msg(!(ci->ci_flags & OCFS2_CACHE_FL_INLINE),
Joel Becker6e5a3d72009-02-10 19:00:37 -0800375 "Owner %llu not marked as inline anymore!\n",
376 (unsigned long long)ocfs2_metadata_cache_owner(ci));
Mark Fashehccd979b2005-12-15 14:31:24 -0800377
378 /* Be careful to initialize the tree members *first* because
379 * once the ci_tree is used, the array is junk... */
Joel Becker47460d62009-02-10 16:05:07 -0800380 for (i = 0; i < OCFS2_CACHE_INFO_MAX_ARRAY; i++)
Mark Fashehccd979b2005-12-15 14:31:24 -0800381 tree[i]->c_block = ci->ci_cache.ci_array[i];
382
Joel Becker47460d62009-02-10 16:05:07 -0800383 ci->ci_flags &= ~OCFS2_CACHE_FL_INLINE;
Mark Fashehccd979b2005-12-15 14:31:24 -0800384 ci->ci_cache.ci_tree = RB_ROOT;
385 /* this will be set again by __ocfs2_insert_cache_tree */
386 ci->ci_num_cached = 0;
387
Joel Becker47460d62009-02-10 16:05:07 -0800388 for (i = 0; i < OCFS2_CACHE_INFO_MAX_ARRAY; i++) {
Mark Fashehccd979b2005-12-15 14:31:24 -0800389 __ocfs2_insert_cache_tree(ci, tree[i]);
390 tree[i] = NULL;
391 }
392
Tao Mad7014852011-02-24 16:22:20 +0800393 trace_ocfs2_expand_cache(
394 (unsigned long long)ocfs2_metadata_cache_owner(ci),
395 ci->ci_flags, ci->ci_num_cached);
Mark Fashehccd979b2005-12-15 14:31:24 -0800396}
397
398/* Slow path function - memory allocation is necessary. See the
399 * comment above ocfs2_set_buffer_uptodate for more information. */
Joel Becker8cb471e2009-02-10 20:00:41 -0800400static void __ocfs2_set_buffer_uptodate(struct ocfs2_caching_info *ci,
Mark Fashehccd979b2005-12-15 14:31:24 -0800401 sector_t block,
402 int expand_tree)
403{
404 int i;
Mark Fashehccd979b2005-12-15 14:31:24 -0800405 struct ocfs2_meta_cache_item *new = NULL;
Joel Becker47460d62009-02-10 16:05:07 -0800406 struct ocfs2_meta_cache_item *tree[OCFS2_CACHE_INFO_MAX_ARRAY] =
Mark Fashehccd979b2005-12-15 14:31:24 -0800407 { NULL, };
408
Tao Mad7014852011-02-24 16:22:20 +0800409 trace_ocfs2_set_buffer_uptodate(
410 (unsigned long long)ocfs2_metadata_cache_owner(ci),
411 (unsigned long long)block, expand_tree);
Mark Fashehccd979b2005-12-15 14:31:24 -0800412
Sunil Mushranafae00ab2006-04-12 14:37:00 -0700413 new = kmem_cache_alloc(ocfs2_uptodate_cachep, GFP_NOFS);
Mark Fashehccd979b2005-12-15 14:31:24 -0800414 if (!new) {
415 mlog_errno(-ENOMEM);
416 return;
417 }
418 new->c_block = block;
419
420 if (expand_tree) {
421 /* Do *not* allocate an array here - the removal code
422 * has no way of tracking that. */
Joel Becker47460d62009-02-10 16:05:07 -0800423 for (i = 0; i < OCFS2_CACHE_INFO_MAX_ARRAY; i++) {
Mark Fashehccd979b2005-12-15 14:31:24 -0800424 tree[i] = kmem_cache_alloc(ocfs2_uptodate_cachep,
Sunil Mushranafae00ab2006-04-12 14:37:00 -0700425 GFP_NOFS);
Mark Fashehccd979b2005-12-15 14:31:24 -0800426 if (!tree[i]) {
427 mlog_errno(-ENOMEM);
428 goto out_free;
429 }
430
431 /* These are initialized in ocfs2_expand_cache! */
432 }
433 }
434
Joel Becker6e5a3d72009-02-10 19:00:37 -0800435 ocfs2_metadata_cache_lock(ci);
Joel Becker8cb471e2009-02-10 20:00:41 -0800436 if (ocfs2_insert_can_use_array(ci)) {
Mark Fashehccd979b2005-12-15 14:31:24 -0800437 /* Ok, items were removed from the cache in between
438 * locks. Detect this and revert back to the fast path */
439 ocfs2_append_cache_array(ci, block);
Joel Becker6e5a3d72009-02-10 19:00:37 -0800440 ocfs2_metadata_cache_unlock(ci);
Mark Fashehccd979b2005-12-15 14:31:24 -0800441 goto out_free;
442 }
443
444 if (expand_tree)
Joel Becker8cb471e2009-02-10 20:00:41 -0800445 ocfs2_expand_cache(ci, tree);
Mark Fashehccd979b2005-12-15 14:31:24 -0800446
447 __ocfs2_insert_cache_tree(ci, new);
Joel Becker6e5a3d72009-02-10 19:00:37 -0800448 ocfs2_metadata_cache_unlock(ci);
Mark Fashehccd979b2005-12-15 14:31:24 -0800449
450 new = NULL;
451out_free:
452 if (new)
453 kmem_cache_free(ocfs2_uptodate_cachep, new);
454
455 /* If these were used, then ocfs2_expand_cache re-set them to
456 * NULL for us. */
457 if (tree[0]) {
Joel Becker47460d62009-02-10 16:05:07 -0800458 for (i = 0; i < OCFS2_CACHE_INFO_MAX_ARRAY; i++)
Mark Fashehccd979b2005-12-15 14:31:24 -0800459 if (tree[i])
460 kmem_cache_free(ocfs2_uptodate_cachep,
461 tree[i]);
462 }
463}
464
Joel Becker6e5a3d72009-02-10 19:00:37 -0800465/* Item insertion is guarded by co_io_lock(), so the insertion path takes
Mark Fashehccd979b2005-12-15 14:31:24 -0800466 * advantage of this by not rechecking for a duplicate insert during
467 * the slow case. Additionally, if the cache needs to be bumped up to
468 * a tree, the code will not recheck after acquiring the lock --
469 * multiple paths cannot be expanding to a tree at the same time.
470 *
471 * The slow path takes into account that items can be removed
472 * (including the whole tree wiped and reset) when this process it out
473 * allocating memory. In those cases, it reverts back to the fast
474 * path.
475 *
476 * Note that this function may actually fail to insert the block if
477 * memory cannot be allocated. This is not fatal however (but may
Mark Fashehaa958872006-04-21 13:49:02 -0700478 * result in a performance penalty)
479 *
480 * Readahead buffers can be passed in here before the I/O request is
481 * completed.
482 */
Joel Becker8cb471e2009-02-10 20:00:41 -0800483void ocfs2_set_buffer_uptodate(struct ocfs2_caching_info *ci,
Mark Fashehccd979b2005-12-15 14:31:24 -0800484 struct buffer_head *bh)
485{
486 int expand;
Mark Fashehccd979b2005-12-15 14:31:24 -0800487
488 /* The block may very well exist in our cache already, so avoid
489 * doing any more work in that case. */
Joel Becker8cb471e2009-02-10 20:00:41 -0800490 if (ocfs2_buffer_cached(ci, bh))
Mark Fashehccd979b2005-12-15 14:31:24 -0800491 return;
492
Tao Mad7014852011-02-24 16:22:20 +0800493 trace_ocfs2_set_buffer_uptodate_begin(
494 (unsigned long long)ocfs2_metadata_cache_owner(ci),
495 (unsigned long long)bh->b_blocknr);
Mark Fashehccd979b2005-12-15 14:31:24 -0800496
497 /* No need to recheck under spinlock - insertion is guarded by
Joel Becker6e5a3d72009-02-10 19:00:37 -0800498 * co_io_lock() */
499 ocfs2_metadata_cache_lock(ci);
Joel Becker8cb471e2009-02-10 20:00:41 -0800500 if (ocfs2_insert_can_use_array(ci)) {
Mark Fashehccd979b2005-12-15 14:31:24 -0800501 /* Fast case - it's an array and there's a free
502 * spot. */
503 ocfs2_append_cache_array(ci, bh->b_blocknr);
Joel Becker6e5a3d72009-02-10 19:00:37 -0800504 ocfs2_metadata_cache_unlock(ci);
Mark Fashehccd979b2005-12-15 14:31:24 -0800505 return;
506 }
507
508 expand = 0;
Joel Becker47460d62009-02-10 16:05:07 -0800509 if (ci->ci_flags & OCFS2_CACHE_FL_INLINE) {
Mark Fashehccd979b2005-12-15 14:31:24 -0800510 /* We need to bump things up to a tree. */
511 expand = 1;
512 }
Joel Becker6e5a3d72009-02-10 19:00:37 -0800513 ocfs2_metadata_cache_unlock(ci);
Mark Fashehccd979b2005-12-15 14:31:24 -0800514
Joel Becker8cb471e2009-02-10 20:00:41 -0800515 __ocfs2_set_buffer_uptodate(ci, bh->b_blocknr, expand);
Mark Fashehccd979b2005-12-15 14:31:24 -0800516}
517
518/* Called against a newly allocated buffer. Most likely nobody should
519 * be able to read this sort of metadata while it's still being
Joel Becker6e5a3d72009-02-10 19:00:37 -0800520 * allocated, but this is careful to take co_io_lock() anyway. */
Joel Becker8cb471e2009-02-10 20:00:41 -0800521void ocfs2_set_new_buffer_uptodate(struct ocfs2_caching_info *ci,
Mark Fashehccd979b2005-12-15 14:31:24 -0800522 struct buffer_head *bh)
523{
Mark Fashehccd979b2005-12-15 14:31:24 -0800524 /* This should definitely *not* exist in our cache */
Joel Becker8cb471e2009-02-10 20:00:41 -0800525 BUG_ON(ocfs2_buffer_cached(ci, bh));
Mark Fashehccd979b2005-12-15 14:31:24 -0800526
527 set_buffer_uptodate(bh);
528
Joel Becker6e5a3d72009-02-10 19:00:37 -0800529 ocfs2_metadata_cache_io_lock(ci);
Joel Becker8cb471e2009-02-10 20:00:41 -0800530 ocfs2_set_buffer_uptodate(ci, bh);
Joel Becker6e5a3d72009-02-10 19:00:37 -0800531 ocfs2_metadata_cache_io_unlock(ci);
Mark Fashehccd979b2005-12-15 14:31:24 -0800532}
533
534/* Requires ip_lock. */
535static void ocfs2_remove_metadata_array(struct ocfs2_caching_info *ci,
536 int index)
537{
538 sector_t *array = ci->ci_cache.ci_array;
539 int bytes;
540
Joel Becker47460d62009-02-10 16:05:07 -0800541 BUG_ON(index < 0 || index >= OCFS2_CACHE_INFO_MAX_ARRAY);
Mark Fashehccd979b2005-12-15 14:31:24 -0800542 BUG_ON(index >= ci->ci_num_cached);
543 BUG_ON(!ci->ci_num_cached);
544
Tao Mad7014852011-02-24 16:22:20 +0800545 trace_ocfs2_remove_metadata_array(
546 (unsigned long long)ocfs2_metadata_cache_owner(ci),
547 index, ci->ci_num_cached);
Mark Fashehccd979b2005-12-15 14:31:24 -0800548
549 ci->ci_num_cached--;
550
551 /* don't need to copy if the array is now empty, or if we
552 * removed at the tail */
553 if (ci->ci_num_cached && index < ci->ci_num_cached) {
554 bytes = sizeof(sector_t) * (ci->ci_num_cached - index);
555 memmove(&array[index], &array[index + 1], bytes);
556 }
557}
558
559/* Requires ip_lock. */
560static void ocfs2_remove_metadata_tree(struct ocfs2_caching_info *ci,
561 struct ocfs2_meta_cache_item *item)
562{
Tao Mad7014852011-02-24 16:22:20 +0800563 trace_ocfs2_remove_metadata_tree(
564 (unsigned long long)ocfs2_metadata_cache_owner(ci),
565 (unsigned long long)item->c_block);
Mark Fashehccd979b2005-12-15 14:31:24 -0800566
567 rb_erase(&item->c_node, &ci->ci_cache.ci_tree);
568 ci->ci_num_cached--;
569}
570
Joel Becker8cb471e2009-02-10 20:00:41 -0800571static void ocfs2_remove_block_from_cache(struct ocfs2_caching_info *ci,
Tao Maac11c822008-08-18 17:38:47 +0800572 sector_t block)
Mark Fashehccd979b2005-12-15 14:31:24 -0800573{
574 int index;
Mark Fashehccd979b2005-12-15 14:31:24 -0800575 struct ocfs2_meta_cache_item *item = NULL;
Mark Fashehccd979b2005-12-15 14:31:24 -0800576
Joel Becker6e5a3d72009-02-10 19:00:37 -0800577 ocfs2_metadata_cache_lock(ci);
Tao Mad7014852011-02-24 16:22:20 +0800578 trace_ocfs2_remove_block_from_cache(
579 (unsigned long long)ocfs2_metadata_cache_owner(ci),
580 (unsigned long long) block, ci->ci_num_cached,
581 ci->ci_flags);
Mark Fashehccd979b2005-12-15 14:31:24 -0800582
Joel Becker47460d62009-02-10 16:05:07 -0800583 if (ci->ci_flags & OCFS2_CACHE_FL_INLINE) {
Mark Fashehccd979b2005-12-15 14:31:24 -0800584 index = ocfs2_search_cache_array(ci, block);
585 if (index != -1)
586 ocfs2_remove_metadata_array(ci, index);
587 } else {
588 item = ocfs2_search_cache_tree(ci, block);
589 if (item)
590 ocfs2_remove_metadata_tree(ci, item);
591 }
Joel Becker6e5a3d72009-02-10 19:00:37 -0800592 ocfs2_metadata_cache_unlock(ci);
Mark Fashehccd979b2005-12-15 14:31:24 -0800593
594 if (item)
595 kmem_cache_free(ocfs2_uptodate_cachep, item);
596}
597
Tao Maac11c822008-08-18 17:38:47 +0800598/*
599 * Called when we remove a chunk of metadata from an inode. We don't
600 * bother reverting things to an inlined array in the case of a remove
601 * which moves us back under the limit.
602 */
Joel Becker8cb471e2009-02-10 20:00:41 -0800603void ocfs2_remove_from_cache(struct ocfs2_caching_info *ci,
Tao Maac11c822008-08-18 17:38:47 +0800604 struct buffer_head *bh)
605{
606 sector_t block = bh->b_blocknr;
607
Joel Becker8cb471e2009-02-10 20:00:41 -0800608 ocfs2_remove_block_from_cache(ci, block);
Tao Maac11c822008-08-18 17:38:47 +0800609}
610
611/* Called when we remove xattr clusters from an inode. */
Joel Becker8cb471e2009-02-10 20:00:41 -0800612void ocfs2_remove_xattr_clusters_from_cache(struct ocfs2_caching_info *ci,
Tao Maac11c822008-08-18 17:38:47 +0800613 sector_t block,
614 u32 c_len)
615{
Joel Becker8cb471e2009-02-10 20:00:41 -0800616 struct super_block *sb = ocfs2_metadata_cache_get_super(ci);
617 unsigned int i, b_len = ocfs2_clusters_to_blocks(sb, 1) * c_len;
Tao Maac11c822008-08-18 17:38:47 +0800618
619 for (i = 0; i < b_len; i++, block++)
Joel Becker8cb471e2009-02-10 20:00:41 -0800620 ocfs2_remove_block_from_cache(ci, block);
Tao Maac11c822008-08-18 17:38:47 +0800621}
622
Mark Fashehccd979b2005-12-15 14:31:24 -0800623int __init init_ocfs2_uptodate_cache(void)
624{
625 ocfs2_uptodate_cachep = kmem_cache_create("ocfs2_uptodate",
626 sizeof(struct ocfs2_meta_cache_item),
Paul Mundt20c2df82007-07-20 10:11:58 +0900627 0, SLAB_HWCACHE_ALIGN, NULL);
Mark Fashehccd979b2005-12-15 14:31:24 -0800628 if (!ocfs2_uptodate_cachep)
629 return -ENOMEM;
630
Mark Fashehccd979b2005-12-15 14:31:24 -0800631 return 0;
632}
633
Adrian Bunk0c6c98f2006-01-07 20:07:02 +0100634void exit_ocfs2_uptodate_cache(void)
Mark Fashehccd979b2005-12-15 14:31:24 -0800635{
636 if (ocfs2_uptodate_cachep)
637 kmem_cache_destroy(ocfs2_uptodate_cachep);
638}