1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
/*-
* See the file LICENSE for redistribution information.
*
* Copyright (c) 1996, 2012 Oracle and/or its affiliates. All rights reserved.
*
* $Id$
*/
#include "db_config.h"
#include "db_int.h"
#include "dbinc/log.h"
#include "dbinc/mp.h"
#include "dbinc/txn.h"
/*
* __memp_dirty --
* Upgrade a page from a read-only to a writable pointer.
*
* PUBLIC: int __memp_dirty __P((DB_MPOOLFILE *, void *,
* PUBLIC: DB_THREAD_INFO *, DB_TXN *, DB_CACHE_PRIORITY, u_int32_t));
*/
int
__memp_dirty(dbmfp, addrp, ip, txn, priority, flags)
DB_MPOOLFILE *dbmfp;
void *addrp;
DB_THREAD_INFO *ip;
DB_TXN *txn;
DB_CACHE_PRIORITY priority;
u_int32_t flags;
{
BH *bhp;
DB_MPOOL *dbmp;
DB_MPOOL_HASH *hp;
DB_TXN *ancestor;
ENV *env;
MPOOL *c_mp;
#ifdef DIAG_MVCC
MPOOLFILE *mfp;
#endif
REGINFO *infop;
int mvcc, ret;
db_pgno_t pgno;
void *pgaddr;
env = dbmfp->env;
dbmp = env->mp_handle;
mvcc = atomic_read(&dbmfp->mfp->multiversion);
/* Convert the page address to a buffer header. */
pgaddr = *(void **)addrp;
bhp = (BH *)((u_int8_t *)pgaddr - SSZA(BH, buf));
pgno = bhp->pgno;
/* If we have it exclusively then its already dirty. */
if (F_ISSET(bhp, BH_EXCLUSIVE)) {
DB_ASSERT(env, F_ISSET(bhp, BH_DIRTY));
return (0);
}
if (flags == 0)
flags = DB_MPOOL_DIRTY;
DB_ASSERT(env, flags == DB_MPOOL_DIRTY || flags == DB_MPOOL_EDIT);
if (F_ISSET(dbmfp, MP_READONLY)) {
__db_errx(env, DB_STR_A("3008",
"%s: dirty flag set for readonly file page", "%s"),
__memp_fn(dbmfp));
return (EACCES);
}
for (ancestor = txn;
ancestor != NULL && ancestor->parent != NULL;
ancestor = ancestor->parent)
;
if (mvcc && txn != NULL && flags == DB_MPOOL_DIRTY &&
(!BH_OWNED_BY(env, bhp, ancestor) || SH_CHAIN_HASNEXT(bhp, vc))) {
atomic_inc(env, &bhp->ref);
*(void **)addrp = NULL;
if ((ret = __memp_fput(dbmfp, ip, pgaddr, priority)) != 0) {
__db_errx(env, DB_STR_A("3009",
"%s: error releasing a read-only page", "%s"),
__memp_fn(dbmfp));
atomic_dec(env, &bhp->ref);
return (ret);
}
if ((ret = __memp_fget(dbmfp,
&pgno, ip, txn, flags, addrp)) != 0) {
if (ret != DB_LOCK_DEADLOCK)
__db_errx(env, DB_STR_A("3010",
"%s: error getting a page for writing",
"%s"), __memp_fn(dbmfp));
atomic_dec(env, &bhp->ref);
return (ret);
}
atomic_dec(env, &bhp->ref);
/*
* If the MVCC handle count hasn't changed, we should get a
* different version of the page.
*/
DB_ASSERT(env, *(void **)addrp != pgaddr ||
mvcc != atomic_read(&dbmfp->mfp->multiversion));
pgaddr = *(void **)addrp;
bhp = (BH *)((u_int8_t *)pgaddr - SSZA(BH, buf));
DB_ASSERT(env, pgno == bhp->pgno);
return (0);
}
infop = &dbmp->reginfo[bhp->region];
c_mp = infop->primary;
hp = R_ADDR(infop, c_mp->htab);
hp = &hp[bhp->bucket];
/* Drop the shared latch and get an exclusive. We have the buf ref'ed.*/
MUTEX_UNLOCK(env, bhp->mtx_buf);
MUTEX_LOCK(env, bhp->mtx_buf);
DB_ASSERT(env, !F_ISSET(bhp, BH_EXCLUSIVE));
F_SET(bhp, BH_EXCLUSIVE);
/* Set/clear the page bits. */
if (!F_ISSET(bhp, BH_DIRTY)) {
#ifdef DIAGNOSTIC
MUTEX_LOCK(env, hp->mtx_hash);
#endif
atomic_inc(env, &hp->hash_page_dirty);
F_SET(bhp, BH_DIRTY);
#ifdef DIAGNOSTIC
MUTEX_UNLOCK(env, hp->mtx_hash);
#endif
}
#ifdef DIAG_MVCC
mfp = R_ADDR(env->mp_handle->reginfo, bhp->mf_offset);
MVCC_MPROTECT(bhp->buf, mfp->pagesize, PROT_READ | PROT_WRITE);
#endif
DB_ASSERT(env, !F_ISSET(bhp, BH_DIRTY) ||
atomic_read(&hp->hash_page_dirty) != 0);
return (0);
}
/*
* __memp_shared --
* Downgrade a page from exlusively held to shared.
*
* PUBLIC: int __memp_shared __P((DB_MPOOLFILE *, void *));
*/
int
__memp_shared(dbmfp, pgaddr)
DB_MPOOLFILE *dbmfp;
void *pgaddr;
{
BH *bhp;
ENV *env;
env = dbmfp->env;
/* Convert the page address to a buffer header. */
bhp = (BH *)((u_int8_t *)pgaddr - SSZA(BH, buf));
if (F_ISSET(bhp, BH_DIRTY))
dbmfp->mfp->file_written = 1;
DB_ASSERT(env, F_ISSET(bhp, BH_EXCLUSIVE));
F_CLR(bhp, BH_EXCLUSIVE);
MUTEX_UNLOCK(env, bhp->mtx_buf);
MUTEX_READLOCK(env, bhp->mtx_buf);
return (0);
}
|
